Half of his bight to b



P. A.-GARDNER.

Steam Generator.'

No. 230,124. Patented July 20,1880.

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MPEYERS, PNOTLLTTHOGRAPHER. WASHINGTON, D C4 UNITED STATES PATENT OEEICE.'

FREDERICK A. GARDNER, OF BUFFALO, NEV YORK, ASSIGNOR OF ONE- HALF OF HIS RIGHT TO R. DUNBAR Qt-SON, OF SAME PLACE.

STEAM-GENERATOR.

SPECIFICATION forming part of Letters Patent No. 230,124, dated July 20, 1880,

Application filed January 8, 1880.

To all whom it may concern:

Beit known that I, FREDERICK ANDREW GARDNER, a subject of the Queen of Great Britain, residing at Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Steam- Generators, of which the following is a specification.

My invention relates to improvements in steam-generators composed of tubing arranged in coils; and it consists, first, of two or more sections of coils of tubes connected in any wellknown way together, so as to form a continuous passage-way from one coil to the other, in combination with a suitable furnace and a circulating-tube arranged at right angles, or nearly so, to the plane of the coils, to which the outer ends of the upper and lower coils are connected, said tube being adapted to receive the water at a point near the bottom from any suitable well-known water-forcing device, and to allow the steam to pass from an opening near the top, and also to allow any water that might separate from the steam to drop to the bottom to be again forced through the genera tor.

The invention further consists in combining with the aforesaid coils a circulating-pipe.

In the accompanying drawings, Figure 1 represents a section through the center of the furnace-case below the top, so as to show a side elevation of the steam-generator, also the coalreservoir and combustion-chamber. Fig. 2 is a plan view of the generator below the top of the furnace; and Fig. 3 represents a vertical longitudinal section through the generator in line X X, as shown in Fig. 2, in which the dotted lines represent where the outer coils and lower inner coils should be connected.-

A represents the furnace-case, which is provided with the ordinary side doors, to give access to the generator or nre-chamber when required. The furnace is also provided with a self-feeding coal-reservoir, B, and the usual damper in the base C.

D represents the lower tubular coil of the generator. It connects with the circulatingtube E at F, from which it curves inward toward the center in the form of a volute, and is then bent upward at G, where it connects with the next coil, G, above it, which is also in the vform of avolute 5 but itis curved from the center outward, and its outer or last coil is curved upward so as to connect with the volute coil of tubing G2 at H, which curves inward toward the center, and is then curved upward so as to connect with the coil G3 at I, which curves outward and connects with the volute coil G4 at J. G4 then curves inward and connects with the upper or top coil, G5, at K. 6o (Shown in dotted lines, Fig. 1, and in the plan view, Fig. 2.) Its outer coil is connected with the tube E, at L.

M in Fig. l represents the collar for the smoke-stack, and N the fire-grate.

It will be noticed that the diameter of the tubes composing the coils gradually becomes smaller from the top coil downward.

If desired, the coils may be all ofone diameter; but I prefer the arrangement shown, as it allows for the expansion of the water as it is forced upward and formed into steam.

The operation of 1n y invention is as follows: Water is forced into the circulatingtube E at P by a force-pump or any other well-known water-forcing device, from which it enters the volute coil D, and passes from the circumference toward the center, and then outward toward the circumference of each alternate coil, until it reaches the circulating-tube E, from which it passes out, in the form of dry steam, in the direction of the arrow Z, into a suitable engine or other receptacle.

In some cases the coal-reservoir B may be dispensed with', especially in localities where coal is scarce and wood abundant.

The circulating-tube E is open from the bottom to the top, but the pressure of thesteam on the water, which is the heaviest, holds it in the circulating-tube at or about the same level with that in the generator, so that as it passes up through the coils it is formed into steam, and becomes lighter and rises, thereby causing a rapid circulation from the bottom of the generator to the top. 95

Should any water escape or condense from the steam at the upper part of the tube E it drops to the bottom and is again forced through the generator.

One advantage in arranging the coils in the roo form of volutes is that it places the tubes in the best possible position to receive the most benefit from the heat as it rises from the fire, and the Water (also the steam) passes nearly on a level through 'each coil in its passage through the generator.

One of the main advantages of my invention is the cheapness and simplicity of the struct- Y ure, resulting from the readiness with which tubes may be coiled, the increased steam-space being secured by'merely using larger tubes.

I-claim- 1. The combination, in a generator, of aireplace, a chamber above the same, and Within said chamber a series of volute coils arranged horizontally, each connected by a pipe exposed v FREDERICK A. GARDNER.

Witnesses J AMns SANGSTER,

GEO'. H. DUNBAR. 

